Avaliação da extração de antocianina de resíduo agroindustrial de amora-preta (Morus nigra) por banho ultrassônico

Abstract

Agro-industrial residues are leftovers from agricultural processes, often discarded in an inappropriate and unusable way, however they can be reused in the production of other products. Some of this waste is made up of raw materials that have coloring properties, such as blackberry peels and pulps. This dyeing is presented through the anthocyanins present in these substrates, and they can be obtained by different extraction methods. In this essay, different solvents and solvent mixtures were evaluated in an Ultrassonic-Assisted Extraction (UAE) of blackberry anthocyanins originated from aggro industrial waste. The total monomeric anthocyanin quantification was made by the pH differential method. The highest anthocyanin comcentration were obtained in systems containing alcoholic solvents, notably isopropanol (6.95 mg/L) and the ethanol-isopropanol mixture (6.12 mg/L). The extract obtained using water showed the lowest concentration (0.75 mg/L). It was also observed that the visual color of the extracts did not correlate directly with the anthocyanin concentration, indicating the influence of other compounds present in the sample. Considering pigment concentration and the resulting color, the water-ethanol mixture showed potential for use as a source of natural colorant. Thus, blackberry agro-industrial residue demonstrated potential for producing extracts containing anthocyanins.